The snowstorm that pummeled much of the U.S. this week ushered in a cold snap, and millions of customers across several states suffered power outages, most of them in Texas.

Texas instituted rolling blackouts across much of the state Wednesday to cope with breakdowns at generating plants and natural-gas-supply problems that prevented some plants from getting fuel.

ENLARGE

James Irlbeck breaks ice at the Irlbeck Cattle feedlot near Amarillo, Texas. This week's storm was followed by unusually cold temperatures.
Associated Press

"This was completely unacceptable," said Mike Walz, a spokesman for Lt. Gov. David Dewhurst, a Republican. "This is an unseasonably cold weather event for Texas, but we need to be prepared regardless and make sure our homes, hospitals, schools and businesses have the electricity they need," he said.

The last time Texas had rolling blackouts was in April 2006, when summer-like weather ramped up air-conditioner use, catching power generators by surprise. Many plants are shut down for maintenance in spring to make sure they are ready for summer, typically the season of highest demand.

Texas officials take pride in the fact that theirs is the only state with its own independently operated power grid and say federal oversight isn't necessary.

In Texas as in most states, residential customers are given priority access to natural-gas supplies during shortages, though a majority of Texans get their heat from electricity.

Some natural-gas pipelines were unable to move gas to power plants because they had lost electricity and "they didn't have a backup system to pressure the lines," said State Sen. Troy Fraser, chairman of the Natural Resources Committee, who plans to hold hearings on the incident.

Some coal plants were unable to provide power to the grid, increasing demand on natural-gas powered generators.

Dottie Roark, spokeswoman for the Electric Reliability Council of Texas, the organization that manages most of the state's electric grid, said about 50 power plants tripped out of service early Wednesday morning. Utilities were ordered to cut off customers, typically for intervals of 15 to 45 minutes, until supply and demand could be brought back into balance.

By Thursday morning, more than 3,000 megawatts of power-generating capacity was still on emergency shutdown. Texas sought help from Mexico and received energy transfers from cities on the border.

Ray Granado, a spokesman for Atmos Energy, the biggest natural-gas distributor in Texas, said a "significant amount of gas we were counting on didn't show up." In some places, he said, the shortfall amounted to half the expected supply.

He said cutbacks would be in effect for industrial customers, including power plants, until supplies return to normal, possibly not until the weekend.

Power officials in several states have expressed concern in recent years about the potential impact of natural-gas disruptions on electricity supplies. In New York, grid officials worked out a process whereby generators can request emergency supplies of natural gas to keep critical facilities operating.

New England confronted the problem in January 2004 after a cold snap threatened fuel supplies.

Elizabeth A. Jones, chairwoman of the Texas Railroad Commission, which has jurisdiction over pipelines, said her agency was looking into the supply disruptions to see if anything should have been done differently.

Despite assurances that local hospitals would not have their power disrupted during the rolling blackouts, at least two hospitals in the Dallas area lost power Wednesday.

Parkland Memorial Hospital, the regional level-one trauma and burn center, lost power at 7 a.m. and again at 9 a.m. for about 20 minutes each time, according to Jorie Klein, Parkand's director of trauma and disaster management. Backup generators immediately kicked in.

Dallas Regional Hospital in the suburb of Mesquite experienced partial outages because a backup generator did not function properly.

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